1. Field of the Invention
The present invention relates generally to filter assemblies and, more particularly, to a flexible filter screen assembly which is capable of being securably attached over an air intake opening of an air filtration, treatment or intake structure of conventional design.
2. Description of the Prior Art
Filtration assemblies are known in the art which can be used in conventional cooling towers and like structures. Normally, such filter assemblies are used for filtering particles from a coolant flow within the cooling tower.
An example of a filtering assembly for an air intake is disclosed in U.S. Pat. No. 5,370,722, issued to Simmons, and which shows a flexible screen positioned to cover an opening of the air intake. The screen includes a top, bottom and first and second side walls and also provides a container located at the base of the structure beneath the intake opening for storing the flexible screen when not in use. A pulley arrangement is provided and which includes cables extending in parallel fashion and in proximity to the first and second sides of the flexible screen. The cables engage the respective sides of the screen by virtue of O-rings which are also secured within eyelets formed along the edges of the sides of the screen and so that the screen may be slidably guided during raising and lowering. An alternate embodiment of the Simmons '722 reference discloses first and second containers secured in parallel extending and opposing arrangement over ends of the air intake opening. A continuous roll of flexible screen material extends between first unused and second used rolls contained in the first and second containers, respectively. An unused portion of the screen is unrolled and advanced over the opening by rotating a crank associated with a selected container and replaces a previously unrolled and used portion which is subsequently rewound onto the second roll.
An additional example of a prior art filtration assembly is disclosed in U.S. Pat. No. 3,695,008, issued to Neumann. The Neumann reference teaches a roller-strip filter for air or gas purification and which, similarly to the second embodiment of the Simmons '722 reference, teaches first and second units for holding feed and wind up rollers for advancing a filter screen.